The present invention relates to tools for forming and cutting sheet metal workpieces and the like.
Machine tools are widely utilized to form sheet metal workpieces into a desired configuration by cooperating upper and lower dies which are configured to provide the contours in the workpiece. The configured forming tool is located in the head of the machine and is moved downwardly against the workpiece which is disposed upon a die that cooperates with the forming tool. Many of such dies have a resiliently deformable portion which facilitates the forming of the metal about the contours of the forming tool. Such tooling may simply deform the workpiece to provide the desired contours and the cooperating surfaces of the components will generally have radiused edges. Other tooling may cut through the workpiece and their components will have sharp cooperating edges to shear the workpiece. Some tooling may provide both forming and cutting action by the providing forming edges about a portion of the periphery and cutting edges about the remainder of the periphery.
The terms “forming” and “forming tools” as used herein encompass tools which merely form the workpiece into a desired configuration, tools which cut through the workpiece, and tools which combine both forming and cutting actions.
Generally, machine tools have a limitation as to the diameter of the forming tool which can be employed. If that diameter of the conventional forming tool is less than the length of the contour to be formed, multiple operations may be required to effect the formation of the full length of the desired contour. This is costly in terms of time required, and it can require use of multiple tools to obtain the desired formation.
It is an object of the present invention to provide a novel forming tool which can be expanded beyond the normal maximum diameter for the forming tool to enable the forming of a workpiece over a wider length.
It is also an object to provide such a forming tool which can be readily and relatively economically fabricated to provide a relatively long lived assembly.